305       UpVal *uv = gco2upv(o);  in reallymarkobject()  local
306       if (upisopen(uv))  in reallymarkobject()
307         set2gray(uv);  /* open upvalues are kept gray */  in reallymarkobject()
309         set2black(uv);  /* closed upvalues are visited here */  in reallymarkobject()
310       markvalue(g, uv->v.p);  /* mark its content */  in reallymarkobject()
376       UpVal *uv;  in remarkupvals()  local
380       for (uv = thread->openupval; uv != NULL; uv = uv->u.open.next) {  in remarkupvals()
381         lua_assert(getage(uv) <= getage(thread));  in remarkupvals()
383         if (!iswhite(uv)) {  /* upvalue already visited? */  in remarkupvals()
384           lua_assert(upisopen(uv) && isgray(uv));  in remarkupvals()
385           markvalue(g, uv->v.p);  /* mark its value */  in remarkupvals()
567     markvalue(g, &u->uv[i].uv);  in traverseudata()
608     UpVal *uv = cl->upvals[i];  in traverseLclosure()  local
609     markobjectN(g, uv);  /* mark upvalue */  in traverseLclosure()
628   UpVal *uv;  in traversethread()  local
638   for (uv = th->openupval; uv != NULL; uv = uv->u.open.next)  in traversethread()
639     markobject(g, uv);  /* open upvalues cannot be collected */  in traversethread()
763 static void freeupval (lua_State *L, UpVal *uv) {  in freeupval()  argument
764   if (upisopen(uv))  in freeupval()
765     luaF_unlinkupval(uv);  in freeupval()
766   luaM_free(L, uv);  in freeupval()